Apparatus and method for monitoring body organs

Abstract

An apparatus and a method for non-invasively measuring oxygen partial pressure in a living body in which light is thrown on a living body to be measured, the oxygen saturation of the living body is obtained from the light absorption spectrum or light scattering spectrum thereof, the temperature and/or pH of the living body is obtained from a nuclear magnetic resonance signal from the living body, and the oxygen partial pressure in the living body, useful for the diagnosis thereof, is determined on the basis of not only the oxygen saturation but also the temperature and/or pH of the living body.

We claim: 
     
       1. A living-body measuring apparatus for measuring the oxygen partial pressure in a living body non-invasively, comprising: means for throwing light on a living body;   means for detecting light having passed through the living body;   means for obtaining the oxygen saturation of an oxygen content indicator substance at a predetermined portion of the living body, from the detected light;   means for generating nuclear magnetic resonance in the living body, to obtain the temperature of the predetermined portion from a first resonance characteristic of the nuclear magnetic resonance;   means for generating nuclear magnetic resonance in the living body, to obtain the acidity of the predetermined portion from a second resonance characteristic of the nuclear magnetic resonance;   means for determining an oxygen partial pressure from the oxygen saturation in accordance with an oxygen dissociation curve of the oxygen content indicator which is compensated with the temperature and the acidity; and   means for displaying the oxygen partial pressure.   
     
     
       2. A living-body measuring apparatus according to claim 1, wherein the means for throwing light on the living body includes a light pulse source, a plurality of first optical couplers adapted to be put in close contact with the living body, and a plurality of first optical fibers connected between the light pulse source and the first optical couplers. 
     
     
       3. A living-body measuring apparatus according to claim 2, wherein the light detection means includes a plurality of second optical couplers adapted to be put in close contact with the living body, a multi-channel, high-speed photodetector, and a plurality of second optical fibers connected between the photodetector and the second optical couplers. 
     
     
       4. A living-body measuring apparatus according to claim 3, wherein said light throwing means and said light detection means are made of a material which makes negligibly small a disturbance in a magnetic field used for obtaining the temperature and acidity of the predetermined portion. 
     
     
       5. A living-body measuring apparatus according to claim 3, wherein in a case where the head of the living body is measured, the first and second optical couplers are attached to a cap adapted to be put in close contact with the head, at positions on the substantially same plane as a slice used in nuclear magnetic resonance measurement for obtaining the temperature and the acidity. 
     
     
       6. A living-body measuring apparatus according to claim 1, wherein said light detection means detects said light after said light has passed through said living-body and been subjected to one of absorption and scattering due to one of a red blood cell and hemoglobin in said living-body. 
     
     
       7. A living-body measuring apparatus according to claim 1, wherein said light detection means detects said light after said light has passed through said living-body and been subjected to one of absorption and scattering due to one of cytochrome and myoglobin in said living-body. 
     
     
       8. A living-body measuring apparatus according to claim 1, wherein the means for obtaining the oxygen saturation determines the oxygen saturation from a light spectrum obtained by the light detection means. 
     
     
       9. A living-body measuring apparatus according to claim 1, wherein said means for generating nuclear magnetic resonance to obtain the temperature of the predetermined portion obtains the temperature of the predetermined portion by determining a longitudinal relaxation time of a first nuclide in the living body. 
     
     
       10. A living-body measuring apparatus to claim 9, wherein said means for generating nuclear magnetic resonance to obtain the temperature of the predetermined portion obtains the temperature of the predetermined portion by determining a longitudinal relaxation time of  1  H in the living body. 
     
     
       11. A living-body measuring apparatus according to claim 9, wherein said means for generating nuclear magnetic resonance to obtain the acidity of the predetermined portion obtains the acidity of the predetermined portion by determining a chemical shift of a second nuclide in the living body. 
     
     
       12. A living-body measuring apparatus for measuring the oxygen partial pressure distribution in a slice of a living body non-invasively, comprising: means for throwing light on a living body;   means for detecting light having passes through the slice of the living body;   means for obtaining the oxygen saturation of an oxygen content indicator substance in the sliced of the living body, from the detected light;   means for generating nuclear magnetic resonance in the slice of the living body, to obtain the temperature distribution in the slice from a first resonance characteristic of the nuclear magnetic resonance;   means for generating nuclear magnetic resonance in the slice of the living body, to obtain the acidity distribution in the slice from a second resonance characteristic of the nuclear magnetic resonance;   means for converting said oxygen saturation distribution into a oxygen partial pressure distribution in said slice in accordance with an oxygen dissociation curve of the oxygen content indicator substance under a standard temperature and under a standard acidity;   means for correcting respective data of the oxygen partial pressure distribution on the basis of differences between the temperature distribution and the standard temperature at respective data points of said slice and of differences between the acidity distribution and the standard acidity of the respective data points; and   means for displaying the oxygen partial pressure distribution corrected with said correcting means as a picture image.   
     
     
       13. A living-body measuring apparatus according to claim 12, further comprising means for displaying the distribution of oxygen partial pressure distribution obtained by said converting means, in the slice of the living body, as a picture image. 
     
     
       14. A living-body measuring apparatus according to claim 13, further comprising means for displaying the temperature distribution in the slice of the living body as a picture image and means for displaying the acidity distribution in the predetermined slice of the living body as a picture image. 
     
     
       15. A living-body measuring apparatus according to claim 14, wherein displaying means displays a picture image showing the distribution of oxygen partial pressure distribution obtained by said converting means, a picture image showing temperature distribution, a picture image showing acidity distribution, and a picture image showing the distribution of oxygen partial pressure having been subjected to temperature correction and acidity correction all at the same time as a single display screen. 
     
     
       16. A living-body measuring method for measuring the oxygen partial pressure in a living body non-invasively, comprising the steps of: throwing light on a living body;   detecting light having passed through the living body;   obtaining the oxygen saturation of an oxygen content indicator substance at a predetermined portion of the living body, from the detected light;   generating nuclear magnetic resonance in the living body, to obtain the temperature of the predetermined portion from a first resonance characteristic of the nuclear magnetic resonance;   generating nuclear magnetic resonance in the living body, to obtain the acidity of the predetermined portion from a second resonance characteristic of the nuclear magnetic resonance;   determining an oxygen partial pressure from the oxygen saturation in accordance with an oxygen dissociation curve of the oxygen content indicator which is compensated with the temperature and the acidity; and   displaying the oxygen partial pressure.   
     
     
       17. A living-body measuring apparatus for measuring the oxygen partial pressure distribution in a slice of living body non-invasively, comprising: means for throwing light on a living body;   means for detecting light having passed through the slice of the living body;   means for obtaining the oxygen saturation distribution of an oxygen content indicator substance in the slice of living body, from the detected light;   means for generating nuclear magnetic resonance in the slice of the living body, to obtain the temperature distribution in the slice from a first resonance characteristic of the nuclear magnetic resonance;   means for generating nuclear magnetic resonance in the slice of the living body, to obtain the acidity distribution in the slice from a second resonance characteristic of the nuclear magnetic resonance;   means for determining an oxygen partial pressure distribution in the slice from the oxygen saturation distribution in accordance with the oxygen dissociation curves of the oxygen content indicator substance which are compensated with the temperature distribution and the acidity distribution; and   means for displaying the oxygen partial pressure distribution as a picture image.